JACKIE STEWART: Ayrton Senna said he’d never speak to me again after I accused him of crashing into Alain Prost to win the title

To mark the 20th anniversary of Ayrton Senna’s death, MailOnline is running a series of features looking back at his Formula One career. Here, Sir Jackie Stewart talks about the famous interview in which he accuses the Brazilian of deliberately crashing into Alain Prost at the Japanese Grand Prix to secure the 1990 World Championship. Phil Duncan listens in.

I had done my homework and Ayrton Senna, at that time, had been involved in more collisions with other drivers than the combined total of all the world champions since 1950. He was agitated, but it could only be someone like me who would be able to put the question to him; someone who had also won three titles.

I truly believed – not for a malicious reason – and was totally convinced that he had intentionally run Alain Prost off the road in Japan, and that is what upset him most. At the following race in Australia, I told him that, and he said, “I can’t believe how somebody like you, would say something like that. I am never going to speak to you again”... and he didn’t for more than a year.

Motor racing had become so safe then. Drivers didn’t, as they currently don’t, understand the dimensions of death because they had never experienced it. In one year, while I was racing, we had experienced one death a month from April to July.

We were going to more funerals and memorial services than you could ever believe. I had been with too many grieving mothers, fathers, brothers, sisters, girlfriends, and seen first-hand the disruption that death causes a family. We were living that, so we had a higher respect; you simply could not take risks. But the tracks had become so safe, drivers were beginning to take liberties and do things like Senna was doing and being involved in the number of collisions that he was, without being killed.

A year had passed since our interview, and I was in Australia for the grand prix when Senna called me. He was a deeply religious man and he said: “Look. I am phoning to apologise because I do now admit that I did take Prost off the road intentionally and God won’t allow me to live this lie. I am going to announce it to the media tonight, but I want you to be the first to know”.

We had a really good conversation on the phone and then he asked if there was any chance I could go over to his hotel and talk about how we could go forward because he wanted to improve safety in Formula One - he knew I had more experience on that issue than anyone else in the sport - so, I did. I went over to his room, and we spent more than two hours together.

Centre of attention: Ayrton Senna turned over a new leaf with regards to safety in Formula One

I was taken aback, but I thought, “Wow, this is great” because he has finally owned up. The fact that he wanted to admit it, and get it out of his system and then take on safety with a new vigour which he had not done before, was a very positive thing. We were on the phone almost every week, twice-a-week in fact, after that conversation in Adelaide until he died at the 1994 San Marino Grand Prix.

Senna had felt as if we needed to re-look at and re-address safety within the sport, because there hadn’t been a fatality in over 12 years, but that didn’t mean to say something would not happen. At that time, for whatever reason, his whole mental attitude towards motor racing changed.

He suddenly was aware that he was being exposed to risks, and wanted to avoid them. That was his maturity evolving from his own experiences and wisdom. He knew I had done that during my career, and if you are world champion, as he was, that carries a lot of attention in the media. If you speak, people will listen. He wanted to be involved.

When Roland Ratzenberger was killed during qualifying at the San Marino Grand Prix, he wanted to go the scene of the accident; he did the same when Martin Donnelly had his huge shunt in 1990. He had started to take a big interest.

Master at work: The Brazilian in action during the Monaco Grand Prix - a track where he won on six occasions

There is no accounting for what happened in Imola. Rubens Barrichello almost had no right to live through his horrendous accident on the Friday. Barrichello was a fellow Brazilian and that must have had an effect on Senna.

For Ratzenberger to be killed on the Saturday and then Senna’s crash the following day, quite frankly, it was calamitous. With Barrichello’s accident, we almost had three grand prix drivers being killed in one weekend over consecutive days after 12-and-a-half years without a fatality. It certainly got the attention of everyone particularly because it was Senna and he was a spectacular and fast driver.

His death had a huge effect on the sport. Professor Sid Watkins was a good friend of Senna’s and a good friend of mine, and he did a great job improving it. If it wasn’t for Sid, half the job wouldn’t have been done. Sid had a huge influence on Bernie Ecclestone and with Max Mosley, who was the president of the FIA.

Professor Sid Watkins, who died in 2012, was well known for his friendship with Senna

It was clear that more could be done. Unfortunately it sometimes takes a death or an accident of that scale, and certainly a weekend like that, for it to happen. But look at the safety of the sport now.

Look at Mark Webber’s accident in Valencia in 2010. Not only did the car turn upside down in the air, but it then went at a huge speed, well over 120mph, into the barrier. I was at home, I was looking at it, and I thought, “Webber can’t survive that”. I thought to myself, “S***, here we go again”, but before you knew it, his head starts to move, then he is out of the car and is walking back to the pits. It was incredible.

Has the sport become blasé in the two decades since that weekend in Imola? I think it has. You can see it with the drivers on the grid - in years past - there was a much more tense atmosphere among them at the beginning of the race.

Now, you can see with all the interviews you get that they are a relaxed bunch of guys because they don’t know what it is to see what happens if something goes wrong. That is a terrible sight and I have seen things that nobody should ever see; just horror stories that will live in my head for ever. That is now not applicable in the sport with any of the drivers - however well they think they know, they don’t.

Different era: The British driver won three Formula One world titles in 1969, 1971 and 1973

There were all sorts of ways we had to deal with life; what it was like then. All the wives of the killed drivers; people don’t understand it. The wives were all helping each other. There was a great unity for these girls to support each other because there were so many incidents. Make no mistake, I have been to a lot of funerals.

I carried the great Juan Manuel Fangio to his last resting place - one of the most important things I have done in my life - and, by the way, I carried Senna to his last resting place, too. A lot of people would have said, “Why is Jackie Stewart there, because Ayrton had said he didn’t want to speak to him?” But we had corrected that.

I was always critical of Senna because, as he said in that interview, if there is a gap you have to go for it, and if you don’t then you are not a great driver. That was wrong. He forced that issue too many times, so I am sorry, I cannot say that he was the greatest Formula One driver.

Laid to rest: Stewart joined Senna's former team-mates' Alain Prost and Gerhard Berger as a pallbearer

In black and white: Stewart speaks to Prost, who he rates a more complete driver than Senna, at the funeral

There were a number of times that he intentionally did things which the great drivers wouldn’t have done. Fangio wouldn’t have done it. Jim Clark wouldn’t have done it. And Prost wouldn’t have done it either.

I rate Prost higher than Senna; the ‘Professor’ was a more complete driver than Senna was. I liked Ayrton a lot as a friend and I loved his enthusiasm and his spirit and his drive, but to be a great you have got to be able to do it with consistency, but he had too many collisions with too many people. Indeed, that would stop Michael Schumacher from being the greatest driver of all time, too.

Senna readily admitted it; winning was what mattered at any cost. Like most people in life however, you mature and that phone call to me was a message that he had done that.